Thomas arthur mccarthy



T. A. McCARTHY.

MECHANICAL CALCULATOR.

.APPLICATION FILED OCT- 23. l9i8.

1,302,941 Patented May 6, 1919.

. UNITED sTATEs PATENT OFFICE.

THOMAS ARTHUR MCCARTHY, F BARBIE, ONTARIO, CANADA.

MECHANICAL CALCULATOR.

Specification of Letters Patent.

Patented May 6, 1919.

To all whom it may concern:

Be it known that I, THOMAS ARTHUR MCCARTHY, a citizen of the United States of America, and a resident of the town of Barrie, county of Simcoe, Province of Ontario, Canada, have invented certain new and useful Improvements in Mechanical Calculators, of which the following is a specification.

My invention relates to improvements in mechanical calculators, and more particularly to that type of mechanical appliance used as an aid in multiplying any given number by any other given number without the transposition of figures and without having to make use of the principle of addition while actually multiplying, as more particularly identified in my U. S. Patent Number 1,276,239, August 20, 1918; and one object of the present invention is to provide a positive means, preferably visible, whereby the operator can accurately determine the columns on the key board of a certain type of adding machine, for example the Burroughs, in which the keys have to be depressed in order to register the product of one number multiplied by another number. Another object of the invention is to provide a device of the class described simpler in construction and cheaper to manufacture than that disclosed in my said United States patent, and which can be used, not only to simplify the multiplication of numbers by those thoroughly familiar with the multiplication table but, also to provide a means whereby the prin ciple of multiplication can be very readily taught.

In the following specification, and drawings forming part thereof, I shall disclose a suitable embodiment within my invention, though it must be understood that the idea as disclosed hereinafter may be embodied in many different forms without departing from the spirit of my invention. Though the device employed to diclose my invention is manually operated, this is not essential.

The form in which my invention is disclosed comprises two members one positioned adjacent the other, longitudinally movable in relation to each other, each of the said members being provided with a plurality of blank spaces designed to receive the multiplier and multiplicand; means for supporting the said members and shifting them, and means whereby the operator can accurately identify any given column on the key-board of the type of adding machine already referred to.

In making use of the device as an aid in multiplying, the required multiplicand is written by hand on one of the said members, and the multiplier written by hand on the other of said members. The left-hand numoral of the multiplier and the right-hand numeral of the multiplicand are placed in alinement, preferably in a vertical relationship, and the product is written down by hand. on paper or mechanically recorded. The very act of positioning the numerals in the multiplier and multiplicand indicates to the operator the column on the keyboard in which a key is first to be depressed. The said numeral in the multiplier and the second figure to the left of the said figure in the multiplicand are then placed in alinement, and the second figure in the multiplier and the first figure in the multiplicand are also placed in alinement. The product of the first pair of figures is written down underneath the first product recorded, one position to the left of the left-hand fi ure of the preceding product, and the proc uct of the third group (and succeeding groups) of figures follows in order, or else these two (and other) products are separately recorded mechanically through the medium of the columns, indicated, on the key-board of the mechanical adding-machine as stated. This operation is carried out until the lefthand figure of the multiplier passes beyond the left-hand figure of themultiplicand, at which time this figure of the multiplier is finished with. Then the user of the device, when manually recording the product of the pairs of numerals to the right of the nu- ,meral just disposed of, will place the first product one position to the right of the lefthand figure of the upper row of figures, and

place the figures of the following products in order until the whole operation has been completed.

It will, of course, be understood that when recording the products mechanically, the operator will at all times, in the class of machine just identified, record the products through the medium of the columns inclicated in the type of mechanical adding ma chine before mentioned.

When recording the products mechanically on a different type of adding machine to that indicated'yfor example by means of the Dalton, the operator must properly space the mechanical adding machineso that the products of the various groups of figures multiplied-will be properly positioned so that when they are added up, the correct product will be secured.

The passing. of .the left-hand figure of the multiplier beyond the left-hand figure of the multiplicand, is a signal to the operator to shift his mechanical adder in certain types of these machines, or to change the position of thenext row of figures in respect of the last'row. of figures recorded, as already setforth.

In using my invention, it' must be under stood. that two-characters must always be put on paper, and, in certain types of adding machines, recordedtherein so as to get the properwposition for. the. various products resulting from the: multiplication of groups of tWo numerals.

Figure 1 is a front elevation of a device within my. invention,-and Fig. 2 is a cross sectionon the'line 2-2, Fig. 1, on an enlargedscale.

In the drawings, like charactersof reference'referto the same parts.

A device within my invention may conveniently comprise a bottom plate or 'memberA, which is suitablycarried by the bracketsB. A bar D is carried by the plate or member A, and preferablydivides the same longitudinally intotwo sections C and E. Also .carri'edby th'eplate or member A, or integrally-formed therewith, are a pair of bars F, and these bars, as Well as the bar I), have. their upper faces positioned above the floors of the sectionsv C and E. The inner edgesof the. bars-F are cut away-to form retaining flanges G against-iwhich track the flarededges-H of the members I and J, which.are mounted in the sections 10 and E respectively, to be 'moved longitudinally thereof; Ilhe'outer faces of the members "I and J aretd-ivided into a; number of spaces a and I), and in these spaces theoperator must write the multiplier and multiplicand.

The said-members are each dividedinto siX spaces inthe example illustrated, though of course they maybe divided into, any number of desired spaces. 'Since-the figures placed on the .sa-id-members-after'zuse will be erased, these members-are made. with their outersurfaces of such material that figures recorded thereon: by lead-pencil, or slate, or chalk, can: be readily removed. For this purpose, I prefer .to -face;-.the -said members with a plateK of slate' or of equivalent material suitably secured thereto,--as by rivets or pins L.

As before set forth, oneof the objects of this invention is to provide the operator with positive means, preferably visible, so that the operator can accurately identify the column onthe key-board of a certain type of adding machine in which the keys have to be depressed in mechanically registering the products of two numbers. My preferred means for'this purpose comprises .a member M suitably secured as by rivets N to the bar D so that the top surface of this member will be flush with the top surfaces of the members I and J. If desired, the member M could be integrally formed part of the bar D. Since in the illustration the spaces a and b are substantially one-half an inch in width, I divide a certain portion of the member M into substantially one-quarter inch spaces 0. The lines (Z separating these spaces always counting from the line 0, indicate the column in the key-board of the certain type of mechanical addingmachine, before identified. In place of the lines cl, numerals from 1 up may be employed, if desired, or other equivalent means of identification. The inner. ends of the spaces a and 5, operating adjacent the bar D, are slightly scored as shown at 7, so as to permit these spaces to be readily brought into alinement through the medium of the lines (Z, and it is for this reason that. I prefer to use these lines in place of-the numerals before mentioned.

The members I and J are preferably positioned one above the other-as shown, and We will suppose that it is desired to multiply the number 687 by the number 978: These numbers are placed in spaces shown in Fig; 1, the last figure in the multiplier and multiplicand always occupying the space at the right-hand end of their respective members, and theother numbers occupying their respective position in the space to the left thereof. By any suitable-means, the space containing the numeral 9 in the multiplier is placed underneath the space containing the numeral 7 in the multiplicand. Multiply these two numbers together, and get a product of 63. This can be placed on paper by hand as shown in the ex-* ample herewith, and when it is desired to mechanically record it in the type of adding machine represented by the Burroughs, since: thespace containing the numeral 9 is underneath one of the scored linesud, the

pressed, and the key in the next columnto I the right thereof-displaying the numeral 3 is depressed, and the machine operated in the ordinary way to record 'the.. same., The space containing. the :numeral 9 is then brought into alinement with the space. contamingthe numeral -8, at which time the-spaces containing the numeral 57 arebroughtv into alinement. Then the product 72 is either placed by hand on paper, or is recorded mechanically as described, in this case compressing the key displaying the numeral 7 in the fifth column on the keyboard, and the key displaying the numeral 2 in the column to the right thereof. The product of 7 multiplied by 7 is then placed by hand on paper, or else recorded mechanically by depressing the key displaying the numeral 4 in the third column on the key-board, and then depressing the key displaying the numeral 9 in the column to the right on the key-board. This operation is carried out until the space containing the numeral 8 is positioned in alinement with the space containing the numeral 6, and these two numbers multiplied, when the operation is completed.

It will, of course, be understood that as each figure in the multiplier passes to the left of the left-hand figure in the multipheand, these figures are discarded, since they have already been used.

When the product in the example in question is recorded by hand, the position of the various products as a result of the multiplying will be as follows:

These products total as above disclosed. In recording the product of the second pair of figures multiplied, this product must be positioned one position to the left of the left-hand numeral of the preceding product, and likewise the product of the third pair of figures. When the space containing the numeral 9 of the multiplier is passed to the left of the space containing the numeral 6 in the multiplicand, as before mentioned, this means that the product of the fourth pair of figures (7 multiplied by 6) will be recorded one position to the right of the left-hand numeral of the next upper line of figures, and the products of the succeeding pairs of numerals will follow in order.

In certain types of mechanical adding machines, two characters must always be utilized therein in the usual way, though in making record by hand on paper this is not always essential. For example, one skilled in the use of the invention in recording by hand, the product of 58 multiplied by 21, according to this method, would not necessarily have to place down the cipher before the numerals 8 and 5, though the use of a' cipher will necessarily always insure proper position of the accompanying numeral.

To shift the members I and J in respect of each other, any suitable means may be employed. In place of shifting these mechanically, they may be shifted manually, though I prefer to utilize some mechanical means for shifting these members. The preferred mechanical means for this purpose comprises a toothed pinion 2 mounted on a stem 3 held in the bottom plate or member A. This stem is provided with a head f to provide for ease of manipulation. Formed in the inner edges of the members I and J are toothed racks 5, with which mesh the toothed pinion 2. Through the manipulation of the means just described, the said members I and J are moved in opposite directions and are easily shifted to effect the object in view.

To allOW for the positioning of the pinion 2, and yet maintain the surfaces of the members I and J flush with the face of the member M, the bar D is interrupted as shown at 6.

The bottom plate or member A, if desired, may be provided with stops 2' to limit the movement of the members I and J.

It will be observed that certain of the lines separating the spaces 0 on the member M, namely every fifth line, are heavier than the other lines. These lines in the device will be made red, thereby assisting the operator in readily locating the desired line (Z required where numerals are not used.

IVhile the spaces a and b are preferably employed, these really, in the broad concep tion of the invention, are not necessary: the use thereof permits the proper spacing between the numerals composing the multiplier and multiplicand so as to prevent confusion in the use of the device.

It will, of course, be understood that, in the broad conception of this invention, the member M, or its equivalent, need not be employed.

Of course, it is within the terms of my invention to keep one of the members I or J stationary, and to move the other. But by moving both members, (preferably simultaneously) the travel thereof is shortened, and consequently the supporting means for these members can be made shorter.

Although I have described, the use of my machine with certain types of adding machines provided with key-boards, still it is within the scope of my invention to embody the principle thereof for use in connection with adding machines, operated by typewriters, such, for example, as the Vahl adding machine.

Claims:

1. A device of the class described com rising two blank members intended to ave placed-thereon, in one case the multiplier cally recording the products.

2. A device of the class described comprising two blank members intended to have and in the other case the multiplicand, and relatively movable so as to bring into alinement the required figures'of the multiplier and'the multiplicand as the solution of the problem proceeds; means supporting said members in cooperative relationship, and

visible means for indicating the columns of the key-board of the given class of mechani cal adding machines to be made use of in mechanically recording the products.

3. A device of the class described comprising two blank members intended to have placed thereon, in one case the multiplier and :in the other case the multiplicand, and a relatively movable so as to bring into alinement the required figures of the multiplier and the multiplicand as the solution of the problem proceeds; means supporting said members in cooperative relationship, and mechanical means for manipulating said members. a

4. A device of the class described comprising two blank members intended to have placed thereon, in one case the multiplier and in the other case the multiplicand, and.

relatively movable so as to bring into alinement'the required fi res of the multiplier and themultiplican as the solution of the problem proceeds; means supporting said members in cooperative relationship, and

means carriedby said support and posi- 4 tioned between said members and provided with indicia whereby the columns of the key-board, of the given class of mechanical adding machine to be made use if in me-c' chanically recording the products, may be indicated.

5. Adevice of the classdescribed compris ing two blank members intended to have placed thereon, in one case the multiplier and in the other case the multiplicand, and relatively'movable so as to bring into alinement the required figures of the multiplier and the multiplicand as the solution of the problem 'proceeds; means supporting said 2 members in cooperative relationship; means carried by said support and positioned between said' members and provided with indicia whereby the columns of the key-board, of the given class of mechanical adding ma- I chine to be made use of in mechanically recording the products, maybe indicated, and mechanical means for manipulating said members'longitudinally each of the other.

6. A device of the class described comprising two blank; members faced with suitable material and divided off; into a plurality of equal spaces, one of said members designed to have placed thereon in the required spaces the multiplier, and the-other of said members designed to have placed thereon in the required spaces the multiplicand; means supporting said members 'in cooperative re lationship; means provided with indicia spaced apart; and carried by said supporting means and positioned between said members, the said indicia'bein'g made use of as the solution as the problem'proceeds to completion, to indicate the columns of the keyboard of thegiven class of mechanical adding machine to bemade'use of in mechani-' cally recordingv the products.

THOMAS ARTHUR MCCARTHY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

